Mining ventilation apparatus and method

ABSTRACT

A method and apparatus for fully ventilating the face of a mined area by means of an auxiliary flow of air which deflects a normal flow of ventilating air such that a relatively greater area of a mine face is contacted by a passing flow of ventilating air.

United States Patent [56] References Cited UNITED STATES PATENTS 6/1956 Sibley.....

[72] Inventor HaroldC.McCleery RD. #1, fianklin, Pa. 16323 Appl. No. 816,224

2,749,105 3,333,896 8/1967 Diamanti......... 3,387,889 6/1968 Ziemba et 1 [22] Filed Apr. 15, 1969 [45] Patented Sept. 7, 1971 Primary Examiner-Ernest R. Purser Attorney-E. Wallace Breisch [54] MINING VENTILATION APPARATUS AND METHOD 12 Claims, 5 Drawing Figs.

[52] 11.5. 299/12, ABSTRACT: A method and apparatus for fully ventilating the 98/50, 299/67 face of a mined area by means of an auxiliary flow of air which [51] Int. E2lc 35/22 deflects a normal flow of ventilating air such that a relatively [50] Field of 299/12, 81; greater area of a mine face is contacted by a passing flow of 98/50 ventilating air.

PATENTED SEP 7 I97! SHEEI 1 [IF 2 m vew ran "41701.0 6: Maze-RY MINING VENTILATION APPARATUS AND METHOD The continuous mining machine of this invention is of the type having one or more rotary cutter heads supported by a vertically movable boom mounted ona mobile base for movement along a mine floor into contact with a mining face developed in a mineral vein. Such mining machines are well known in the art and the particular machine to which the structure and method of the instant inventionapply is more fully shown and described in copending application Ser. No. 786,650 filed Dec. 24, 1968 (Teeter) which application is assigned to the same assignee as is this application.

It is well known that miners of the continuous type whether rotary cutting head, boring machines or chain-type ripper miners all have a tendency to stir up a great deal of dust. The object of the present invention is to provide a current of auxiliary air directed at the point of greatest dust production to augment the normal air flow which by a suitable partitioning of the mined passageway is constrained to travel toward the face along one part of the passageway, across the mine face and outwardly along the mine passage on the side of the machine away from the operator to reduce the dust and gas hazard normally present in the use of continuous miners.

The particular advantages of the ducts incorporated in the boom according to this invention are as follows:

With the fan and ducts made integral with the boom no separate supporting mechanism or duct-swinging mechanism is necessary to keep the air source suitably positioned;

Because the ducts are integral with the boom once the aiming of the outlet mouth has been accomplished adjustment of the boom up and down carries the ducts with it and keeps the outlet adjustment proper for aiming the current of air at the point of greatest gas liberation and dust production;

With the air aimed at that particular point superior dust removal and gas dilution take place as compared to the action of a more generally supplied air current.

These and other advantages and objects of this invention will become more readily apparent upon consideration of the following description and drawings in which:

FIG. 1 is a general three-dimensional view of a mining machine constructed according to the principles of this invention;

FIG. 2 is a top plan view ofthe mining machine of FIG. 1;

FIG. 3 is a side elevational view of the mining machine of FIGS. 1 and 2;

FIG. 4 is a sectional view taken substantially on line 44 of FIG. 2 looking in the direction indicated by the arrows;

FIG. 5 is a sectional view taken substantially on line 5-5 of FIG. 2 and looking in the direction of the arrows.

Referring now to the drawings, in FIG. 1 there is shown a mining machine generally indicated at having a cutter head drum 24 rotatably mounted on a vertically movable boom 18 which is pivotally mounted on a main frame 16 in turn supported and rendered movable over a surface by a pair of crawler assemblies 14 in a manner well known in the art. The main frame 16 also supports an elongated, centrally located flight conveyor 30 and a conventional loader arm-type gathering head 26 all as more fully shown and described in the above cited copending application of Teeter. The cutter support boom 18 is pivotally supported as at 38 and pivotable about a horizontal axis by the action of fluid operated extensible jacks 32 while the gathering head is similarly pivotable in the vertical direction by a pair of suitable jacks 34.

Centrally mounted in a rearward portion of the boom 18 is a ducted fan and motor assembly 27 which may be of any type suitable for moving large quantities of air at moderate velocities. The housing of the fan assembly 27 is fitted to and communicates in substantially airtight relationship with a generally Y-shaped rectangular air duct 28 having rightand left-hand branches 36 and 37, respectively, suitably sized having a cross-sectional area approximately twice that of the fan to conduct the air delivered by the fan and motor assembly 27 at a moderate velocity through either of two branches 36 and 37 of the Y-duct 28. As shown the branches of 36 and 37 of the Y-duct 28 extend diagonally forwardly and outwardly from the front end of the fan assembly 27 through the interior of the boom 18 with the outermost ends of the branches 36 and 37 protruding outwardly beyond the sides of the boom 18. At either of the outboard ends of the Y-duct 28 there is a substantially full cross section opening 29 to deliver the air from the fan and motor assembly 27. As best seen in FIGS. 2 and 5 a substantially rectangular valve of damper element 35 is positioned across the base of the left-hand branch 37 to stop the flow of air therethrough and direct all of the airflow into the right branch as hereinafter explained. As shown in FIG. 5 the damper 35 is secured in position by a single retaining element such as a capscrew 39 located somewhat to the right of the longitudinal centerline of the boom with the damper 35 extending diagonally rearwardly across that centerline to mate with the rear side of the left branch. For some purposes it is desirable to shut off the right branch 36 instead of the left and for this purpose a threaded bore 40 is provided in a position analogous to that of the capscrew 39 but to the left of the boom centerline. By moving the capscrew 39 from its present position to the bore 40 and at the same time swinging the damper 35 into a mating position therewith, across the right branch 36, the switch of air flow can be made. As best seen in FIG. 3 and shown in detail in FIG. 4 the outboard ends of the duct 28 are tipped downwardly so that the openings 29 point approximately tangent to the outer surface of cutter head drum 24 at its underside for a purpose to be described.

The cutter head drum 24 supports helical conveyor members on which are mounted suitable mineral cutting bits (not shown) which when operating travel in paths collectively forming an outline shown as a bit path 25 to cut mineral in a well-known manner.

In operation the particular machine 10 hereinabove described is brought to a mineral face by operation of the crawler assemblies 14 in a well'known manner and with the boom raised and the cutter head drum rotating in a clockwise direction as seen in FIG. 3 the miner It) begins to form a new face as at 23 (see FIG. 3). As soon as the cutting begins at the desired top level or roof line 20 the machine is moved forward approximately half the diameter of the bit path 25 and the boom is then gradually lowered with the formation of a face 23 somewhat as seen in FIG. 3 with a substantially horizontal portion 23' being continuously formed and continuously cut away. This face portion 23 is subject to the highest rate of cutting action of any part of the face area. Since maximum cutting takes place in the substantially level area 23 this is also the place where the greatest amount of dust is formed and the greatest amount of gas is liberated. With the damper 35 set in the position indicated in FIG. 2 the left hand branch 37 of the duct 28 is blocked so that all of the air from the fan and motor assembly 27 must travel through the right-hand branch 36 of the duct 28 and out the right-hand opening 29. With the outer end of the duct 28 and the opening 29 pointed at the space between the drum head 24 and the face portion 23' air from the fan and motor assembly 27 strikes the shelflike portion 23 and mingles with the dust and gas, diluting the gas and pushing the dust backward toward the face and with the air all being directed to the right-hand side of the face, pressure there becomes higher than at the left-hand side and as a consequence the air moves across the face from right to left (bottom to top as seen in FIG. 2) and striking the left-hand wall or rib 2 is forced to travel backwardly along the machine until it passes behind a movable partition such as a brattice 31 spaced outwardly from rib 21 a sufficient distance to give a reasonable passageway for the air from the fan and motor assembly 27 with its load of dust and gases intermixed. Some of the dust of course will fall to the floor 22 of the mine but in general the finer particles and the admixed gas will be carried along behind the orattice 31 to the general mine ventilating system from which it will be exhausted and disposed of in a suitable manner.

It is to be well noted that with the ducts 28 mounted in, movable with, and supported by the boom 18 the openings 29 are always in position, relative to the level portion 23' of the face 23 to, deliver the blast of air at exactly the proper point regardless of whether the machine is cutting high or cutting low.

The above described mining machine b oom with a particular duct system is but one of many possible structures capable of practicing the ventilation method of this invention which could be generally described as follows: during mining machine operation within a mine passageway there is generally provided a normal supply flow of air along the passageway to the face portion on one side of the passageway centerline, across the face and away from the face in retreat flow on the other side of the centerline by one of several ex pedients such as a brattice located near one rib extending almost to the face and having a negative pressure (i.e. lower than atmospheric) behind the brattice the air then would generally move toward the face along the mine passageway and then away from the face behind the brattice or as otherwise described; the air could also be taken away from the face by a large duct continuously extended to keep the intake end of it ahead of the operator to prevent dust from falling on the operator; to continue with the method of this invention; with the normal supply flow of air along the passageway toward the face the method of this invention contemplates discharging an auxiliary air stream at an acute angle to and in concurrent flow with the normal supply flow which air stream will be an input flow of sufficient volume and velocity to deflect the supply flow over portions of the face not normally contacted by such supply flow, particularly including the corner of the face which normally would be a dead air space without benefit of the gas dilution and dust removal of the normal flow of air over other portions of the face; further steps of the method could be included in varying the direction of the discharge of the auxiliary air stream from a high angle at the beginning of the cutting cycle (sumping portion) and continuously varying the angles from that high angle down to a low angle directed obliquely toward the floor of the mine at the end of the downward sheer action so that during the complete cutting cycle the auxiliary air stream is directed toward the area of greatest gas liberation and dust production to dilute the gas and carry away the dust in an augmented retreat flow of air, gas and dust mixture away from the face.

It is further to be noted that if it is desired to use a reverse airflow technique with the fan and motor assembly 27 blowing toward the back of the machine it would be reasonable to switch the damper 35 from the position shown in H6. 2 to an analogous position in which the right-hand branch of the duct 28 is blocked by the damper 35 so that air from the right-hand side of the face will still travel across the left-hand side of the face where it will be scooped in by the opening 29 through the duct 28 and the fan and motor assembly 27 to delivered rearwardly probably by way of a flexible pipe (not shown). Thus accomplishing the purposes of this invention and utilizing the principles thereof particularly the positioning of the openings 29 always in the proper relation to the cutting surface 23' and such arrangement is within the scope of this invention.

With the damper 35 entirely removed it is, of course, possible to utilize both branches 36 and 37 for either supplying air to the face or removing the dust and gas mixture therefrom as another application of the principles of this invention.

Other arrangements are of course possible with air being supplied through both openings 29 and taken away behind brattices perhaps on both sides of the machine or even picked up by overhead mounted conduits of various design.

A preferred embodiment of the method and structure ofthis invention having hereinabove been described with certain obvious variations thereon it is to be realized that other variations are possible without departing from the scope of this invention. It is therefore respectfully requested that this invention be interpreted as broadly as possible.

What is claimed is: 1. ln a mining machine of the type having a cutter head mounted on the free forward end of an elongated boom and which cutter head extends laterally outwardly from each side of said boom and is movable in conjunction with said boom across a face of a bedded deposit of mineral, the improvement comprising: air conducting passageway means carried by said boom and movable therewith; said passageway means having a discharge opening located to discharge air outwardly of one side of said boom and forwardly towards the end of said cutterhead in closest proximity thereto; and means for causing air flow through said passageway means.

2. A mining machine as specified in claim 1 wherein said passageway means includes a second discharge opening located to discharge air outwardly of the other side of said boom and forwardly towards the other end of said cutterhead.

3. A mining machine as specified in claim 2 additionally comprising flow control means cooperable with said passageway means to control the discharge of air through said discharge openings.

4. The mining machine as specified in claim 3 wherein said flow control means is a damper type valve movably mounted within said passageway means.

5. The mining machine as specified in claim 2 wherein said passageway means includes a Y-shaped air duct and said discharge openings are at the ends of respective furcations of said duct opposite the juncture ends thereof.

6. The mining machine as specified in claim 5 wherein said means for causing airflow is a fan and motor combination.

7. The mining machine as specified in claim 6 wherein said fan is a ducted axial flow fan mounted within the single leg portion of said air duct.

8. The method of ventilating the mine face during the operation of a mining machine within a mine passageway, comprising: continuously providing along one side of a mine passageway a first flow of air toward a mine face located at the inner end of said passageway; continuously maintaining flow of at least a portion of said first flow towards the intersection of said one side and said face by directing an auxiliary flow of air at an acute angle to and in concurrent flow with said first flow; and thereafter withdrawing all of said air flows across said face and outwardly of said passageway.

9. The method of ventilating as specified in claim 8 in which the operation of the mining machine includes a face-shearing cycle, including the further step of continuously varying the vertical orientation of said auxiliary flow in said passageway in conjunction with the progression of said face-shearing cycle.

it). The method of ventilating as specified in claim 9 wherein said varying of said vertical orientation is substantially coincident with the portion of the face being sheared.

11. A mining machine as specified in claim 1 additionally comprising flow control means cooperable with said passageway means to control the discharge of air through said discharge opening.

12. A method of ventilating as specified in claim 8 including, prior to said withdrawing, the additional steps of: discontinuing said first flow of air; selectively providing a second flow of air toward said face along the other side of said passageway; and selectively directing said auxiliary flow of air at an acute angle to and in concurrent flow with said second flow. 

1. In a mining machine of the type having a cutter head mounted on the free forward end of an elongated boom and which cutter head extends laterally outwardly from each side of said boom and is movable in conjunction with said boom across a face of a bedded deposit of mineral, the improvement comprising: air conducting passageway means carried by said boom and movable therewith; said passageway means having a discharge opening located to discharge air outwardly of one side of said boom and forwardly towards the end of said cutterhead in closest proximity thereto; and means for causing air flow through said passageway means.
 2. A mining machine as specified in claim 1 wherein said passageway means includes a second discharge opening located to discharge air outwardly of the other side of said boom and forwardly towards the other end of said cutterhead.
 3. A mining machine as specified in claim 2 additionally comprising flow control means cooperable with said passageway means to control the discharge of air through said discharge openings.
 4. The mining machine as specified in claim 3 wherein said flow control means is a damper type valve movably mounted within said passageway means.
 5. The mining machine as specified in claim 2 wherein said passageway means includes a Y-shaped air duct and said discharge openings are at the ends of respective furcations of said duct opposite the juncture ends thereof.
 6. The mining machine as specified in claim 5 wherein said means for causing airflow is a fan and motor combination.
 7. The mining machine as specified in claim 6 wherein said fan is a ducted axial flow fan mounted within the single leg portion of said air duct.
 8. The method of ventilating the mine face during the operation of a mining machine within a mine passageway, comprising: continuously providing along one side of a mine passageway a first flow of air toward a mine face located at the inner end of said passageway; continuously maintaining flow of at least a portion of said first flow towards the intersection of said one side and said face by directing an auxiliary flow of air at an acute angle to and in concurrent flow with said first flow; and thereafter withdrawing all of said air flows across said face and outwardly of said passageway.
 9. The method of ventilating as specified in claim 8 in which the operation of the mining machiNe includes a face-shearing cycle, including the further step of continuously varying the vertical orientation of said auxiliary flow in said passageway in conjunction with the progression of said face-shearing cycle.
 10. The method of ventilating as specified in claim 9 wherein said varying of said vertical orientation is substantially coincident with the portion of the face being sheared.
 11. A mining machine as specified in claim 1 additionally comprising flow control means cooperable with said passageway means to control the discharge of air through said discharge opening.
 12. A method of ventilating as specified in claim 8 including, prior to said withdrawing, the additional steps of: discontinuing said first flow of air; selectively providing a second flow of air toward said face along the other side of said passageway; and selectively directing said auxiliary flow of air at an acute angle to and in concurrent flow with said second flow. 